[mnhloot]

I know there are some car guru's that lurk here, I was wondering if I could get some advice on what might be causing my car to randomly not start. I have a shitty 1995 Toyota Camry.
Randomly, although it seems to happen more often in colder weather, my car will not start. When I turn the key, the engine keeps clicking, but never turns over. If I let it sit a couple of hours, and usually by this time, the sun is out and things are warming up, it'll start no problems.

Things i'v had replaced (Not all of them related to this problem):
Fuel pump
Water pump
Timing belt
Thermometer
Catalytic converter
Head gasket
Battery

So far my only guess is the starter and/or alternator. But what leads me to believe it isn't those, is, once the car starts, it's fine (also awhile ago, I had diagnostics run on the battery, starter and alt - they all *checked out*). When it isn't starting, the sound of the engine revving, but not turning over is not like the sound you'd hear from a dead battery or anything, as even trying to jump the car does nothing. Like I mentioned, it seems to be related to cold and warm weather. I guess it might also be the distributor cap/housing?
Any ideas?

Thanks in advance